Exposing the Delocalized Cu−S π Bonds on the Au 24 Cu 6 (SPh t Bu) 22 Nanocluster and Its Application in Ring‐Opening Reactions

Bimetallic nanomaterials are of major importance in catalysis. A Au‐Cu bimetallic nanocluster was synthesized that is effective in catalyzing the epoxide ring‐opening reaction. The catalyst was analyzed by SCXRD and ESI‐MS and found to be Au 24 Cu 6 (SPh t Bu) 22 (Au 24 Cu 6 for short). Six copper atoms exclusively occupy the surface positions in two groups with three atoms for each, and each group was bonded with three thiolate ligands to give a planar motif reminiscent of a benzene ring. In the epoxide‐ring opening reaction, Au 24 Cu 6 exhibited superior catalytic activity compared to other homometallic and Au‐Cu alloy NCs, such as Au 25 and Au 38− x Cu x . Control experiments and DFT calculations revealed that the π conjugation among the Cu−S bonds played a pivotal role. This study demonstrates a unique π conjugation established among the Cu−S bonds as a critical structural motif in the nanocluster, which facilitates the catalysis of a ring‐opening reaction.